llvm-project/llvm/tools/llc/llc.cpp

327 lines
11 KiB
C++

//===-- llc.cpp - Implement the LLVM Native Code Generator ----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This is the llc code generator driver. It provides a convenient
// command-line interface for generating native assembly-language code
// or C code, given LLVM bitcode.
//
//===----------------------------------------------------------------------===//
#include "llvm/Bitcode/ReaderWriter.h"
#include "llvm/CodeGen/FileWriters.h"
#include "llvm/CodeGen/LinkAllCodegenComponents.h"
#include "llvm/CodeGen/LinkAllAsmWriterComponents.h"
#include "llvm/Target/SubtargetFeature.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetMachineRegistry.h"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Module.h"
#include "llvm/ModuleProvider.h"
#include "llvm/PassManager.h"
#include "llvm/Pass.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/FileUtilities.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/PluginLoader.h"
#include "llvm/Support/RegistryParser.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Analysis/Verifier.h"
#include "llvm/System/Signals.h"
#include "llvm/Config/config.h"
#include "llvm/LinkAllVMCore.h"
#include <fstream>
#include <iostream>
#include <memory>
using namespace llvm;
// General options for llc. Other pass-specific options are specified
// within the corresponding llc passes, and target-specific options
// and back-end code generation options are specified with the target machine.
//
static cl::opt<std::string>
InputFilename(cl::Positional, cl::desc("<input bitcode>"), cl::init("-"));
static cl::opt<std::string>
OutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename"));
static cl::opt<bool> Force("f", cl::desc("Overwrite output files"));
static cl::opt<bool> Fast("fast",
cl::desc("Generate code quickly, potentially sacrificing code quality"));
static cl::opt<std::string>
TargetTriple("mtriple", cl::desc("Override target triple for module"));
static cl::opt<const TargetMachineRegistry::entry*, false,
RegistryParser<TargetMachine> >
MArch("march", cl::desc("Architecture to generate code for:"));
static cl::opt<std::string>
MCPU("mcpu",
cl::desc("Target a specific cpu type (-mcpu=help for details)"),
cl::value_desc("cpu-name"),
cl::init(""));
static cl::list<std::string>
MAttrs("mattr",
cl::CommaSeparated,
cl::desc("Target specific attributes (-mattr=help for details)"),
cl::value_desc("a1,+a2,-a3,..."));
cl::opt<TargetMachine::CodeGenFileType>
FileType("filetype", cl::init(TargetMachine::AssemblyFile),
cl::desc("Choose a file type (not all types are supported by all targets):"),
cl::values(
clEnumValN(TargetMachine::AssemblyFile, "asm",
"Emit an assembly ('.s') file"),
clEnumValN(TargetMachine::ObjectFile, "obj",
"Emit a native object ('.o') file [experimental]"),
clEnumValN(TargetMachine::DynamicLibrary, "dynlib",
"Emit a native dynamic library ('.so') file"
" [experimental]"),
clEnumValEnd));
cl::opt<bool> NoVerify("disable-verify", cl::Hidden,
cl::desc("Do not verify input module"));
// GetFileNameRoot - Helper function to get the basename of a filename.
static inline std::string
GetFileNameRoot(const std::string &InputFilename) {
std::string IFN = InputFilename;
std::string outputFilename;
int Len = IFN.length();
if ((Len > 2) &&
IFN[Len-3] == '.' && IFN[Len-2] == 'b' && IFN[Len-1] == 'c') {
outputFilename = std::string(IFN.begin(), IFN.end()-3); // s/.bc/.s/
} else {
outputFilename = IFN;
}
return outputFilename;
}
static raw_ostream *GetOutputStream(const char *ProgName) {
if (OutputFilename != "") {
if (OutputFilename == "-")
return &outs();
// Specified an output filename?
if (!Force && std::ifstream(OutputFilename.c_str())) {
// If force is not specified, make sure not to overwrite a file!
std::cerr << ProgName << ": error opening '" << OutputFilename
<< "': file exists!\n"
<< "Use -f command line argument to force output\n";
return 0;
}
// Make sure that the Out file gets unlinked from the disk if we get a
// SIGINT
sys::RemoveFileOnSignal(sys::Path(OutputFilename));
std::string error;
raw_ostream *Out = new raw_fd_ostream(OutputFilename.c_str(), true, error);
if (!error.empty()) {
std::cerr << error << '\n';
delete Out;
return 0;
}
return Out;
}
if (InputFilename == "-") {
OutputFilename = "-";
return &outs();
}
OutputFilename = GetFileNameRoot(InputFilename);
bool Binary = false;
switch (FileType) {
case TargetMachine::AssemblyFile:
if (MArch->Name[0] == 'c') {
if (MArch->Name[1] == 0)
OutputFilename += ".cbe.c";
else if (MArch->Name[1] == 'p' && MArch->Name[2] == 'p')
OutputFilename += ".cpp";
else
OutputFilename += ".s";
} else
OutputFilename += ".s";
break;
case TargetMachine::ObjectFile:
OutputFilename += ".o";
Binary = true;
break;
case TargetMachine::DynamicLibrary:
OutputFilename += LTDL_SHLIB_EXT;
Binary = true;
break;
}
if (!Force && std::ifstream(OutputFilename.c_str())) {
// If force is not specified, make sure not to overwrite a file!
std::cerr << ProgName << ": error opening '" << OutputFilename
<< "': file exists!\n"
<< "Use -f command line argument to force output\n";
return 0;
}
// Make sure that the Out file gets unlinked from the disk if we get a
// SIGINT
sys::RemoveFileOnSignal(sys::Path(OutputFilename));
std::string error;
raw_ostream *Out = new raw_fd_ostream(OutputFilename.c_str(), Binary, error);
if (!error.empty()) {
std::cerr << error << '\n';
delete Out;
return 0;
}
return Out;
}
// main - Entry point for the llc compiler.
//
int main(int argc, char **argv) {
llvm_shutdown_obj X; // Call llvm_shutdown() on exit.
cl::ParseCommandLineOptions(argc, argv, "llvm system compiler\n");
sys::PrintStackTraceOnErrorSignal();
// Load the module to be compiled...
std::string ErrorMessage;
std::auto_ptr<Module> M;
std::auto_ptr<MemoryBuffer> Buffer(
MemoryBuffer::getFileOrSTDIN(InputFilename, &ErrorMessage));
if (Buffer.get())
M.reset(ParseBitcodeFile(Buffer.get(), &ErrorMessage));
if (M.get() == 0) {
std::cerr << argv[0] << ": bitcode didn't read correctly.\n";
std::cerr << "Reason: " << ErrorMessage << "\n";
return 1;
}
Module &mod = *M.get();
// If we are supposed to override the target triple, do so now.
if (!TargetTriple.empty())
mod.setTargetTriple(TargetTriple);
// Allocate target machine. First, check whether the user has
// explicitly specified an architecture to compile for.
if (MArch == 0) {
std::string Err;
MArch = TargetMachineRegistry::getClosestStaticTargetForModule(mod, Err);
if (MArch == 0) {
std::cerr << argv[0] << ": error auto-selecting target for module '"
<< Err << "'. Please use the -march option to explicitly "
<< "pick a target.\n";
return 1;
}
}
// Package up features to be passed to target/subtarget
std::string FeaturesStr;
if (MCPU.size() || MAttrs.size()) {
SubtargetFeatures Features;
Features.setCPU(MCPU);
for (unsigned i = 0; i != MAttrs.size(); ++i)
Features.AddFeature(MAttrs[i]);
FeaturesStr = Features.getString();
}
std::auto_ptr<TargetMachine> target(MArch->CtorFn(mod, FeaturesStr));
assert(target.get() && "Could not allocate target machine!");
TargetMachine &Target = *target.get();
// Figure out where we are going to send the output...
raw_ostream *Out = GetOutputStream(argv[0]);
if (Out == 0) return 1;
// If this target requires addPassesToEmitWholeFile, do it now. This is
// used by strange things like the C backend.
if (Target.WantsWholeFile()) {
PassManager PM;
PM.add(new TargetData(*Target.getTargetData()));
if (!NoVerify)
PM.add(createVerifierPass());
// Ask the target to add backend passes as necessary.
if (Target.addPassesToEmitWholeFile(PM, *Out, FileType, Fast)) {
std::cerr << argv[0] << ": target does not support generation of this"
<< " file type!\n";
if (Out != &outs()) delete Out;
// And the Out file is empty and useless, so remove it now.
sys::Path(OutputFilename).eraseFromDisk();
return 1;
}
PM.run(mod);
} else {
// Build up all of the passes that we want to do to the module.
ExistingModuleProvider Provider(M.release());
FunctionPassManager Passes(&Provider);
Passes.add(new TargetData(*Target.getTargetData()));
#ifndef NDEBUG
if (!NoVerify)
Passes.add(createVerifierPass());
#endif
// Ask the target to add backend passes as necessary.
MachineCodeEmitter *MCE = 0;
switch (Target.addPassesToEmitFile(Passes, *Out, FileType, Fast)) {
default:
assert(0 && "Invalid file model!");
return 1;
case FileModel::Error:
std::cerr << argv[0] << ": target does not support generation of this"
<< " file type!\n";
if (Out != &outs()) delete Out;
// And the Out file is empty and useless, so remove it now.
sys::Path(OutputFilename).eraseFromDisk();
return 1;
case FileModel::AsmFile:
break;
case FileModel::MachOFile:
MCE = AddMachOWriter(Passes, *Out, Target);
break;
case FileModel::ElfFile:
MCE = AddELFWriter(Passes, *Out, Target);
break;
}
if (Target.addPassesToEmitFileFinish(Passes, MCE, Fast)) {
std::cerr << argv[0] << ": target does not support generation of this"
<< " file type!\n";
if (Out != &outs()) delete Out;
// And the Out file is empty and useless, so remove it now.
sys::Path(OutputFilename).eraseFromDisk();
return 1;
}
Passes.doInitialization();
// Run our queue of passes all at once now, efficiently.
// TODO: this could lazily stream functions out of the module.
for (Module::iterator I = mod.begin(), E = mod.end(); I != E; ++I)
if (!I->isDeclaration())
Passes.run(*I);
Passes.doFinalization();
}
// Delete the ostream if it's not a stdout stream
if (Out != &outs()) delete Out;
return 0;
}